1 // triangle.cxx -- "Triangle" interface class
3 // Written by Curtis Olson, started March 1999.
5 // Copyright (C) 1999 Curtis L. Olson - curt@flightgear.org
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 // (Log is kept at end of this file)
25 #include "triangle.hxx"
26 #include "tripoly.hxx"
30 FGTriangle::FGTriangle( void ) {
35 FGTriangle::~FGTriangle( void ) {
39 // populate this class based on the specified gpc_polys list
40 int FGTriangle::build( const FGgpcPolyList& gpc_polys ) {
42 // traverse the gpc_polys and build a unified node list and a set
43 // of Triangle PSLG that reference the node list by index
46 gpc_polygon *gpc_poly;
47 const_gpcpoly_iterator current, last;
49 // process polygons in priority order
50 cout << "prepairing node list and polygons" << endl;
52 for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
53 cout << "area type = " << i << endl;
54 current = gpc_polys.polys[i].begin();
55 last = gpc_polys.polys[i].end();
56 for ( ; current != last; ++current ) {
58 cout << "processing a polygon, contours = "
59 << gpc_poly->num_contours << endl;
63 if (gpc_poly->num_contours <= 0 ) {
64 cout << "FATAL ERROR! no contours in this polygon" << endl;
68 if (gpc_poly->num_contours > 1 ) {
69 cout << "FATAL ERROR! no multi-contour support" << endl;
74 for ( int j = 0; j < gpc_poly->num_contours; j++ ) {
75 for ( int k = 0; k < gpc_poly->contour[j].num_vertices; k++ ) {
76 Point3D p( gpc_poly->contour[j].vertex[k].x,
77 gpc_poly->contour[j].vertex[k].y,
79 index = trinodes.unique_add( p );
81 // cout << index << endl;
83 poly.calc_point_inside( trinodes );
85 polylist[i].push_back(poly);
90 for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
91 if ( polylist[i].size() ) {
92 cout << get_area_name((AreaType)i) << " = "
93 << polylist[i].size() << endl;
100 // do actual triangulation
101 int FGTriangle::do_triangulate( const FGTriPoly& poly ) {
102 trinode_list node_list;
103 struct triangulateio in, out;
106 // define input points
107 node_list = trinodes.get_node_list();
109 in.numberofpoints = node_list.size();
110 in.numberofpointattributes = 0;
111 in.pointlist = (REAL *) malloc(in.numberofpoints * 2 * sizeof(REAL));
113 trinode_list_iterator current, last;
114 current = node_list.begin();
115 last = node_list.end();
117 for ( ; current != last; ++current ) {
118 in.pointlist[counter++] = current->x();
119 in.pointlist[counter++] = current->y();
126 // triangulate each of the polygon areas
127 int FGTriangle::triangulate() {
129 struct triangulateio in, out;
131 trinode_list node_list = trinodes.get_node_list();
134 in.numberofpoints = node_list.size();
135 in.numberofpointattributes = 1;
136 in.pointlist = (REAL *) malloc(in.numberofpoints * 2 * sizeof(REAL));
138 trinode_list_iterator tn_current, tn_last;
139 tn_current = node_list.begin();
140 tn_last = node_list.end();
142 for ( ; tn_current != tn_last; ++tn_current ) {
143 in.pointlist[counter++] = tn_current->x();
144 in.pointlist[counter++] = tn_current->y();
147 in.pointattributelist = (REAL *) NULL;
148 in.pointmarkerlist = (int *) NULL;
151 in.numberofsegments = 0;
153 tripoly_list_iterator tp_current, tp_last;
154 for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
155 cout << "area type = " << i << endl;
156 tp_current = polylist[i].begin();
157 tp_last = polylist[i].end();
158 for ( ; tp_current != tp_last; ++tp_current ) {
160 in.numberofsegments += poly.size() + 1;
164 in.numberofsegments = 0;
166 in.numberofholes = 0;
167 in.numberofregions = 1;
168 in.regionlist = (REAL *) malloc(in.numberofregions * 4 * sizeof(REAL));
169 in.regionlist[0] = 0.5;
170 in.regionlist[1] = 5.0;
171 in.regionlist[2] = 7.0; /* Regional attribute (for whole mesh). */
172 in.regionlist[3] = 0.1; /* Area constraint that will not be used. */
175 tripoly_list_iterator current, last;
176 for ( int i = 0; i < FG_MAX_AREA_TYPES; ++i ) {
177 cout << "area type = " << i << endl;
178 current = polylist[i].begin();
179 last = polylist[i].end();
180 for ( ; current != last; ++current ) {
182 cout << "triangulating a polygon, size = " << poly.size() << endl;
184 do_triangulate( poly );
193 // Revision 1.6 1999/03/20 13:22:11 curt
194 // Added trisegs.[ch]xx tripoly.[ch]xx.
196 // Revision 1.5 1999/03/20 02:21:52 curt
197 // Continue shaping the code towards triangulation bliss. Added code to
198 // calculate some point guaranteed to be inside a polygon.
200 // Revision 1.4 1999/03/19 22:29:04 curt
201 // Working on preparationsn for triangulation.
203 // Revision 1.3 1999/03/19 00:27:10 curt
204 // Continued work on triangulation preparation.
206 // Revision 1.2 1999/03/18 04:31:11 curt
207 // Let's not pass copies of huge structures on the stack ... ye might see a
210 // Revision 1.1 1999/03/17 23:51:59 curt